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Finding the Fourth Proportional to 20.61, 30.81 and 16.05

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Solution

The fourth proportional to 20.61, 30.81 and 16.05 is: 23.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.61 : 30.81 = 16.05 : x
  2. Step 2: Convert to fraction form
    20.61/30.81 = 16.05/x
  3. Step 3: Cross multiply
    20.61x = 30.81 × 16.05
  4. Step 4: Simplify right side
    20.61x = 494.50
  5. Step 5: Solve for x
    x = 494.50/20.61
  6. Step 6: Final answer
    x = 23.99

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.